<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div th:text="${session.aaa}"></div>
<form action="/alipay.html" method="post">
    金额<input name="amount"/>
    <input type="submit" value="提交"/>
</form>
</body>
</html>